We are big fans of analgesia in Virchester. Pain is an important reason why patients come to the ED (though not the only reason see this), and managing pain should be an important priority for us and our patients. In general I think we have improved over the years. We have better systems for identifying pain at triage (use of pain scores) and early intervention aimed at reducing pain for out patients. That’s all fantastic but pain once initially vanquished often recuperates and returns. How good are we are managing on-going pain? Do our patients initially thank us for the analgesia yet wonder if we have a good strategy for keeping them pain free.
In Virchester we have increased our use of Patient Controlled Analgesia (PCA) in recent years. Typically this is for patients with conditions where we know there are ongoing analgesia requirements. We have a long established use of PCA for patients with vaso-occlusive sickle crisis and for those with pancreatitis, but it’s a little haphazard and by no means widespread. Typically pain is managed using an ‘on-demand’ process.
- Patient in pain
- Patient gets initial analgesia management
- Patient gets pain again
- Patient requests analgesia
- Prescription written
- Drugs found
- Analgesia given
Obviously there are many flaws in this. Patients have to ask, staff have to be available and in all honesty this is a reactive rather than a pro-active approach to pain. Why should we wait for pain to recur before treating. Perhaps we should generally prevent recurrence and deliver adequate analgesia to reduce the peaks and troughs of intermittent analgesia. PCAs clearly have the potential to do this for our ED patients.
Prof. Jason Smith is an old friend of St.Emlyn’s and a really interesting emergency physician based in the South West of England. He recently led a team of researchers looking at the use of PCAs in emergency medicine. Two RCTs have been published in the BMJ. Abstracts are below and these are both currently open access. Make sure you read the full papers.
For those who don’t know the South West of England you may not be familiar with the term PASTIES. A pasty is a pastry filled with meat and vegetables and are traditionally made in Cornwall which is where the trial is based. Surely one of the tastier trial acronyms of recent years.
Two randomised controlled trials looking at ED patients with painful conditions. Both trials took pragmatic open label approaches randomising patients to either a PCA or standard care. Although two trials are published the methodology and delivery of the protocols is essentially identical, performed in the same departments and with the same research team.
Patients reported pain scores on an hourly basis
Non traumatic abdominal pain trial
This trial recruited 200 adult patients who required intravenous opiates to manage their initial pain. Those in the PCA group had statistically less overall pain with fewer patients in the PCA group experiencing subsequent severe or moderate pain. Overall it’s a win for PCA.
Traumatic pain trial
This trial recruited 200 patients with traumatic injury requiring opiate analgesia in the ED. In contrast to the abdominal pain trial there was no statistically significant difference in this trial. There was a very small trend towards benefit in the PCA group but the clinical significance of the effect size is probably unimportant.
These studies are good examples of pragmatic trials in emergency settings. The broad range of participants, study sites and researchers makes it easier to translate the findings to clinical practice in Virchester. The RCT design is entirely appropriate and the nature of the intervention means that blinding (masking) is not really possible. I particularly like the fact that these trials followed patients beyond the emergency department. It is all too easy to confine our considerations and trials as they relate to the emergency department, but patients are transiting the ED, not remaining in it (current overcrowding issues aside).
The difference in outcomes between the traumatic and non-traumatic trials is interesting and perhaps reflects the underlying pathological processes. Analgesia in traumatic injury can be achieved through pharmacological and non-pharmacological means whereas in abdominal pain non-pharmacological methods are less available and more difficult to achieve. In addition abdominal pain may be a progressive inflammatory process as opposed to traumatic injury where pain typically peaks soon after injury.
PCA thus offers an improvement in patient experience for those presenting to the ED with abdominal pain. As clinicians these papers mean that we should be considering the use of PCAs in a greater range of patients than we currently do.
FCEM critical appraisal style questions
1. Comment on the primary outcome measure of overall pain over 12 hours. What other outcomes would influence your decision to adopt PCA for patients in the ED.
2. How could the lack of blinding influence the principle outcome of this trial?